<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>mycss</title>
    <link rel="stylesheet" href="mycss.css">
</head>
<body>
<div class="d1">div1</div>
<div class="d2">div2</div>
<div class="d3">
    div3 <span class="c1">in div3</span>
</div>
<div class="d4">
    div4 <span class="c2">in div4</span>
</div>
<div class="d5">div5</div>
</body>
</html>